Preparation of YSZ film by EPD and its application in SOFCs

An electrophoretic deposition (EPD) method was applied for the preparation of yttria-stabilized zirconia (YSZ) thin film on a NiO-YSZ porous anode substrate for solid oxide fuel cell (SOFC) applications. Dense YSZ film with uniform thickness can be readily prepared with the EPD method using isopropanol as solvent and iodine as dispersant. As EPD electrode, the NiO-YSZ substrate was covered with a graphite layer to obtain enough electric conductivity. A series of experiments, such as suspension concentration, sintering shrinkage, and so on, were conducted in order to optimize the EPD technique. A planar-type SOFC was fabricated using La_0.4Sr_0.6Co_0.2Fe_0.8O₃ (LSCF) as the cathode and YSZ film deposited onto the NiO-YSZ anode substrate as the electrolyte. The fuel cell exhibited an open circuit voltage of about 1.0 V and a maximum power density of 440 mW/cm² at 900 °C. Thus, the EPD method was a suitable technology for the formation of gas-tight YSZ film.